"Changing out parts for different effect has nothing to do with so-called burn in. The same issue would apply."
Like I said, don't take my word for it. Call some manufacturers and see what they say. |
As I see it, it can be expected that by the time developmental testing is completed on the prototype of a new design, including final tweaking/voicing of the design, the prototype is likely to have accumulated a MUCH greater number of hours of operation than production units accumulate prior to leaving the factory. Both as a matter of necessity, due to the nature of the development process, and because the designer will want to assure that final tweaking/voicing takes into account any possible breakin phenomena.
Therefore if in fact breakin phenomena occur for a given design over a number of operating hours that is greater than the number of hours of operation of production units prior to shipment from the factory, those phenomena will continue to occur after the component is placed in service by the end user. And the component will not perform as its designer intended until after some period of use by the end user.
I would be very surprised if any of that were not the case, particularly when it comes to speakers, cartridges, AND major electronic components. So I am in essential agreement with ZD on this point.
Regards,
-- Al |
06-22-14: Zd542
"Ok lets say things do change after "burn in", how does any designer compensate for this, in his calibrations, measurements, tests and design????"
They compensate for this by breaking the prototypes in before they listen and measure. For example, a designer may want to try several different capacitors when building an amp to see which one sounds the best. If they want to try 5 different options, they break the amp in 5 different times. They don't do any serious listening or measurements until they break the amp in first. This is the way they all do it. I don't think you could find one company that doesn't break their equipment like this. You don't have to take my word for it, either. Call some manufactures and ask them. Ok if this is true, then this means all production units sent out that are not "burnt in" have been purposely miss-adjusted/calibrated for currents, bias, dc offset etc, NOT for the best ideal performance. Hoping then that all these parameters of adjustments will all come together after the customer has "burnt it in" for a few weeks??? I think not. Cheers George |
On the contrary, the units are built to the spec that is finally agreed upon. It's just that anything new will not remain so and will alter over time until it's "broken" in.
Just because something is electric in nature and we can't see it doesn't mean that's there's no aging: wear and tear so to speak, over the short term. It's a big learning curve and we are just on the upward part of that curve.
I'm curious as to this: if we all experienced and agreed that the burn in was of a universally short nature, say a day or so, that there'd be general agreement. Using that as a priori, would it be so difficult to consider that some things take longer?
All the best,
Nonoise |
It makes no sense that the expectation is for parts to fall out of spec in order to fall into a desired lower cumulative level of performance. Ridiculous. And how would this be accomplished within a reasonable time frame? By using inferior quality parts? Again, ridiculous. |
06-22-14: Csontos
It makes no sense that the expectation is for parts to fall out of spec in order to fall into a desired lower cumulative level of performance. Ridiculous. And how would this be accomplished within a reasonable time frame? By using inferior quality parts? Again, ridiculous. Exactly, when a unit is tested and adjusted up before it leaves the factory, it should stay this way for some time, for years we all hope. To say that components change their characteristics after this because of "burn in" hours, means those adjustments will out out of spec, after the burn in. Brand new capacitors do what's called "form" but this only takes minutes and they should already be "formed" by the time it takes to do the final spec adjustments in the factory before shipping. The only thing in audio I know of that degrades relatively quickly from the first time it's switched on is tubes. And if they don't have auto bias circuits to keep them in spec, they need to be measured and adjusted every now and again. As they do loose the bias adjustment, depending on how many hours they are on. Cheers George |
A stupid attempt at lending credence to the notion that wires and cables have a wacky ability to magically alter performance. |
Interconnects can sometimes alter things, all are different in construction, and parameters such as impedance, capacitance and inductance, of the cable can have filtering effects when used on high output impedance devices, such tube preamps and passive volume controls.
But anyone who says they need "burning in" with burn in gadgets and burn in cd's needs to be taken with a grain of salt.
Cheers George |
It makes no sense that the expectation is for parts to fall out of spec in order to.... That was never said or implied. All that was is that things don't stay new. Tubes aren't the only things that age due to heating up. Anything electricity encounters the slows down it's travel heats it up. So cold, out of the box won't and can't sound the same as when on for awhile. A really stupid attempt... Really? Is this baggage from some older thread? Nothing I know of sounds best, functions best, drives best, or operates best until broken in. Please name one thing that does.Then there is a long period of great performance. To say that it only doesn't apply to electronics is goofy, to be polite. The signal doesn't magically travel through cables, capacitors, tubes, traces and the like and not leave a trace or have an affect. That affect is the lessening of the time it takes to sound it's best. All the best, Nonoise |
I get that certain technical specs are sometimes required and that there is a descending scale of quality. I was referring to the unmeasurables. You know, those invisible attributes that always exponentially increase cost more than materials and labor. |
Nonoise, you didn't take that personally, did you? I was of course generalizing. No offense. |
Infer, imply, suggest. Call it what you will but I know what I read. Perhaps you misread the previous post? |
Csontos, I didn't know what to take and am sorry if I inferred incorrectly.
No harm, no foul.
All the best,
Nonoise |
George & Peter (Csontos), I would respectfully disagree with what appears to be the logic behind your recent posts, at least with respect to electronic components (amps, preamps, digital sources, etc). It seems to me that implicit in your logic are the following assumptions:
1)The alleged breakin phenomena which you dispute would result in changes that are measurable, at the component level (as distinguished from the piece part level).
2)As long as the component measures within the +/- tolerances defined by its specifications it will sound as the designer intended, meaning that it will sound the same as his or her prototype sounded when its development was completed.
3)Therefore for the alleged breakin phenomena which you dispute to exist, the component must measure outside of the +/- tolerances defined by its specifications when it is delivered to the customer.
In the case of electronic components I see no reason to expect any of those assumptions to be true.
Regards,
-- Al |
I get that, Al. I read an inference suggesting a below spec target goal in order to achieve the desired end result. It was disputed but I don't buy it. In terms of "measurable", I was referring to wires and cables as I'm sure you recognize. All in all, I think it went well:) |
The effect of burn in on dielectric materials and how it affects the dielectric constant is well understood and can be found all over the Internet by a simple Google, so you can just about ignore all the hoopla surrounding burn in of cables, anything with wires side, capacitors, transformers, things in that vein. |
George is right.
But you need to let your computer screen break in to fully understand the concept. |
So Al, by disagreeing respectfully, are you saying that you believe that "breakin phenomena" does exist??
Or just to my assumptions that there should be a measurable difference in component specification?
And if so, in which do you believe the "breakin phenomena" exists, passive cables or active electronic components?
Cheers George |
George, what I was disagreeing with were the three assumptions I listed that your disagreement with ZD appeared to be based on. As far as my own beliefs are concerned, I think we are all agreed that speakers, cartridges, and tubes will change their behavior significantly as they break in. Beyond that I cant particularly speak from experience, as the only major components Ive bought new in many years have been speakers. But since youve asked, FWIW my beliefs concerning other kinds of components, and cables and power cords, are as follows:
1)I have made the point in dozens of threads over the years here that it is extremely easy in audio to attribute a perceived change to the wrong variable. And I believe that many reported perceptions of changes due to break in, especially those involving many hundreds of hours, are the result of incorrect attribution, made possible by experimental methodology which is not adequately thorough and disciplined. Of course, I also assume that in a significant number of cases such reports are simply the result of misperception. And all of that is fostered by a goodly amount of what I perceive to be mythology and technical misconception that is pervasive in audio.
2)Concerning electronic components (solid state as well as tube), as I said I cant speak from experience. However, a considerable majority of those audiophiles whose opinions I have come to particularly respect, and who also have vast amounts of experience with excellent equipment, believe based on that experience that new electronic components generally require a breakin period of at least tens of hours, and in many cases hundreds of hours. While my technical background and my understanding of how this stuff works does not enable me to precisely explain that, it also does not provide me with any definitive reason to refute it. Therefore I believe that solid state and tube electronic components can be expected to undergo significant amounts of breakin, perhaps several hundred hours for some components.
As I implied earlier in the thread, however, my strong suspicion when I see reports of 800 or 1000 hours or thereabouts being necessary is that either there has been a misperception, or something else has changed in the system or its AC power or its environment (e.g., temperature or humidity, as we both cited earlier in the thread).
3)Concerning cables and power cords, I would say that Im somewhere in the skeptical part of the spectrum, but I dont completely rule out the possibility. Among various explanations that tend to be offered, effects related to the dielectric, such as dielectric absorption, are perhaps the most commonly cited. However I have never seen any QUANTITATIVE analysis or measurements offered which would either establish or negate the possibility that such effects may be great enough in degree to have a reasonable chance of being audibly significant. It is very easy to conjure up explanations when they are not, or as a practical matter can not be, subjected to quantitative scrutiny.
The bottom line: As with most things in life, I believe that the truth depends on the specifics that are being considered, and generally lies somewhere in the middle part of the ideological spectrum.
IMO, YMMV, FWIW, etc.
Regards,
--Al |
So it seems like we are in agreement, that to us "break in" for better or worse can occur with the mechanical devices such as speakers drivers, cartridges, and tubes, as you also said.
And you and I will not commit without skirting around the edges and state to "break in" periods of semiconductors or active components can get "better sounding" with said "break in" times of 100's of hours, unless some technical proof is brought forward, forgetting hearsay of friends and customers.
Cheers George |
There is a certain semi-conductor I do believe undergoes burn in, but as an exception to the rule. And I seriously look forward to yours, George, and Al's comments on this. I've brought up the offset and bias trim pots which are variable resistors, on a couple of other threads but not in regards to this topic. I'm suggesting that because they are always adjusted after recap/refurb, that the perceived short term progressive improvement heard even with new gear is a result of the wiper contact on the pad of the trim pot 'seating' and thus improving it's contact point until optimal and it is this action that is being tracked sonically by the user. The change is real but simply mis-attributed to stationary components. I regularly experience this phenomenon. It's easily observable and you George may be able to relate to this as the same issue pertains to basic mechanical attenuators. The very issue your own product addresses. On a single turn trim pot where you have direct contact with the wiper against your screw driver, you can press on it at the point of correct adjustment and hear improvement. Leave it alone and it will slowly reach that same quality over the short term. I incidentally noticed this a long time ago as another position I hold on bias adjustment requires that I do that procedure while listening. Sq has always continued to improve for up to a month or so after I adjust offset/bias pots. I'm thinking this has to be some how measurable. Without knowing the specifics as I don't recall the text, volume pots have contact issues such that optimization is apparently next to impossible and I'm hoping George can speak on this. |
I know this won't be good enough, but I'll try one last time.
This is directly out of the manual for my Ayre V-5.
"Break-In
100 to 500 hours of music
played through the system will
ensure full break-in.
Due to the manufacturing processes used for the
printed circuit boards, wires, and capacitors, a
break-in period is necessary for the amplifier to
reach its full performance potential."
Here's one from Pass Labs.
"Amplifiers
Do the amps need to break in. Yes. Most improvement comes in the first 24-36 hours, after which the amps will continue to improve as long as they are left on.
Preamplifiers
How long do the preamps need to break in?
That depends. The XP-10, XP-20 and XP-15 need about 24 hours to fully warm up. The XP-25 and XP-30 take closer to 36 hours. After initial warm up period the preamps will continue to improve as long as they are left on."
If you want more examples like this, there are thousands. All you have to do is look for them. If you read reviews from magazines like TAS and Stereophile, break in details are included in almost every equipment review they publish. (I haven't read reviews for about 10 years now. I'm assuming they still talk about break in.). You can also call a manufacturer directly. They are usually happy to answer any break in questions pertaining to their equipment.
Other that that, I don't know what more I can offer on this topic. |
06-23-14: Georgelofi
So it seems like we are in agreement, that to us "break in" for better or worse can occur with the mechanical devices such as speakers drivers, cartridges, and tubes, as you also said.
And you and I will not commit without skirting around the edges and state to "break in" periods of semiconductors or active components can get "better sounding" with said "break in" times of 100's of hours, unless some technical proof is brought forward, forgetting hearsay of friends and customers. George, that is not quite what I said. Note particularly item no. 2 in my previous post, which is entirely consistent with what is stated in the references ZD cited just above. Peter (Csontos), the potentiometer-related effect you described certainly strikes me as being plausible, and a clever observation, but my suspicion is that it is just one of a great many effects that can occur. Best regards, -- Al |
"ZD cited just above." Is again not a technical explaination. Could conscrewed as getting used to the sound so you don't take it back for refund.
As for trimpots Peter (Csontos), yes if they are left in one position for a while they do tend to loose contact between the wiper contact point (metalic), and track (carbon or conductive plastic) because of current flow between dissimilar materials.
Part of the same reason for the Lightspeed Attenuator, no contacts of dissimilar materials (diode effect). When ever I see this, I take out the single turn trimpots and replace with Bourns multiturn, they last a bit longer but still have the same problem after a while. Maybe we should use the Lightspeed system as bias pots as well, now you've given me another idea.
Cheers George |
I'd love to try that George. |
